Oil and/or gas wells are generally produced through a conventional well tubing which include a plurality of interconnected threaded sections along with conventional production completion equipment. However, in the event that there is a failure in the production equipment, the well is killed, the entire production well tubing may be required to be removed, repaired and replaced which is an expensive and time-consuming operation requiring the use of an oil rig, and the well flow is restarted. In addition the well may be damaged.
The present invention is directed to recompleting existing oil and/or gas wells by utilizing coil tubing which along with accessories can be installed in the existing well tubing, can be utilized in a live well without killing the well, and which can provide recompletion of the well with less time and expense than conventional operations.
Coil tubing is a continuous conduit without joints carried on a reel which can be lowered into well tubing, and is of a small diameter such as 1 to 11/2 inches. Coil tubing has been used in the past for injecting well fluids into well tubing, sand washing, and removal of liquids from the well, and producing wells through a free hanging length of tubing.
The present invention is directed to a method and apparatus to install a coil tubing into an existing well tubing and includes a variety of accessories such as a hydraulic control tubing safety valve, a hydraulic control annular safety valve, gas lift valves and mandrels, hydraulic control latches, and hydraulically actuated well packers along with the necessary hydraulic control lines.